He's been sitting on a plane for hours, waiting for takeoff

Doug Behm has been sitting on a Jet Blue flight bound for Cartagena, Colombia, for hours. He shared a photo of passengers standing restlessly in the plane's center aisle.

"Was supposed to leave at 7.51 AM," Behm tweeted. "Taxied for a while, then back to the gate to refuel. Delayed due to staffing issues caused by the Government shutdown."

Nearly three hours after his flight was supposed to take off, Behm told CNN the plane was still stuck at the gate at John F. Kennedy Airport.

"Haven't gotten an update in a while," he said.

Here's the scene inside the plane:

Dough Behm

11:17 a.m. ET, January 25, 2019

This expert is concerned some air traffic controllers are "not fit for duty"

Asked by CNN's Jim Sciutto whether the airport delays are a direct result of the government shutdown, Trish Gilbert, Executive Vice President of the National Air Traffic Controllers Association said, "Absolutely."

"We predicted that you cannot continue to operate a system this complex for this long without the support structure of the people that are furloughed," Gilbert said.

While Gilbert doesn't know the details of every absence, she said there are concerns that stress and a lack of sleep could mean some air traffic controllers aren't able to do their jobs.

"We are already short-staffed," she said. "So now you've added the stress to air traffic controllers and their personal circumstances. And they're not sleeping at night. Now we're concerned that they're not fit for duty."

President Trump has been briefed on the airport delays

White House Press Secretary Sarah Sanders said in statement that President Trump has been briefed on the airport delays.

"The President has been briefed and we are monitoring the ongoing delays at some airports," Sanders said. "We are in regular contact with officials at the Department of Transportation and the FAA."

10:44 a.m. ET, January 25, 2019

Political officials think air travel issues could be the key to ending the shutdown

From CNN's Kevin Liptak, Kaitlan Collins and Jeremy Diamond

It’s too early to say whether widespread flight delays at major East Coast airports will break the shutdown stalemate. But the prospect of a national air travel meltdown has long loomed in the minds of White House and congressional officials as the one thing that might bring an end to the stalemate.

Administration officials have said as recently as this week that if the shutdown began to devastate air travel, they feared Republicans would jump ship and get on board with a short-term Democratic plan to reopen the government.

And it’s not just inside the White House. Outside political advisers to President Trump and his allies on Capitol Hill have worried major flight issues would amplify the blame Trump is already facing for the shutdown. They, too, believe that major disruptions to air travel would ramp up pressure to reopen the government without wall funding

As the shutdown has worn on, Trump has been focused on two particular areas where Americans might be affected, according to people familiar with this thinking: Air travel and tax returns.

He has asked aides whether Transportation Security Administration and Federal Aviation Administration workers are breaking laws by calling out sick, likening it to the air traffic controllers strike during the Reagan administration.

10:43 a.m. ET, January 25, 2019

Ground stop at LaGuardia is expected for another hour

From CNN's Rene Marsh

There is a ground stop at New York City's LaGuardia Airport right now. The ground stop will go on for about another hour, according to an FAA spokesman.

The ground stop was ordered as a way to clear congestion caused by the staffing issues and the resulting slowdown of traffic.

10:42 a.m. ET, January 25, 2019

Philadelphia airport experiencing delays of more than an hour

Philadelphia International Airport tweeted that the FAA is reporting departure delays of 1 hour and 14 minutes.

10:38 a.m. ET, January 25, 2019

She's sitting on a plane in Atlanta, waiting to take off for New York City

From CNN's Gianluca Mezzofiore

Joy Burney is sitting on Delta flight 2927, from Atlanta to New York City's LaGuardia Airport.

That flight has been delayed because of staffing issues with air traffic control.

"My flight was supposed to take off at 9:30," she told CNN. "(Our) departure time was updated 3 times. Originally, we were told there was a delay at LaGuardia. They thought maybe they were de-icing planes since planes were grounded."

10:33 a.m. ET, January 25, 2019

FAA: We're experiencing "a slight increase in sick leave"

From CNN's Rene Marsh

The Federal Aviation Administration just sent out a statement on the flight delays happening in the Northeast right now:

"We have experienced a slight increase in sick leave at two air traffic control facilities affecting New York and Florida. As with severe storms, we will adjust operations to a safe rate to match available controller resources. We’ve mitigated the impact by augmenting staffing, rerouting traffic, and increasing spacing between aircraft as needed. The results have been minimal impacts to efficiency while maintaining consistent levels of safety in the national airspace system."

It added that travelers can monitor air traffic here, and check with airline carriers.

10:30 a.m. ET, January 25, 2019

Staffing shortages cause delays at 3 Northeast airports

From CNN's Greg Wallace

Air traffic is delayed at LaGuardia, Philadelphia, and Newark airports due to staffing issues at an FAA regional air traffic control center, according to the FAA status website.

Here's what the delays look like:

Flights into Philadelphia, La Guardia and Newark airports are delayed by an average of 41 minutes.

Departing flights from Philadelphia and Newark are delayed between an hour and an hour and 15 minutes